Python获取字典中的值的八种方法

dictionary = {"key1": "value1", "key2": "value2"}
value = dictionary["key1"]
print(value)  # 输出 value1

dictionary = {"key1": "value1", "key2": "value2"}
value = dictionary.get("key1")

#定义一个字典
my_dict ={"name":"Tom","age":18,"gender":"male"}

#获取字典中"name”键对应的值
value = my_dict.get("name")
print(value)  #输出:Tom
#获取字典中"phone"键对应的值，由于"phone"不存在，返回 None
value = my_dict.get("phone")
print(value)  #输出:None

dictionary = {"key1": "value1", "key2": "value2"}
for key in dictionary.keys():
    print(key)  # 输出 key1  key2

dictionary = {"key1": "value1", "key2": "value2"}
for value in dictionary.values():
    print(value)

dictionary = {"key1": "value1", "key2": "value2"}
for key, value in dictionary.items():
    print(key)     # 输出key
    print(value)   # 输出 value

#定义一个字典
my_dict ={"name":"Tom","age":18,"gender":"male"}

# 判断 name 是否在字典中
if "name" in my_dict:
    print("name is in my_dict")
# 判断 phone 是否在字典中
if "phone" in my_dict:
    print("phon is in my_dict")
else:
    print("phone is not in my_dict")

#定义一个字典
my_dict ={"name":"Tom","age":18,"gender":"male"}

# 删除字典中 age 中对应的值，并返回对应的值

value=my_dict.pop("age")
print(value)    #  18
print(my_dict)   # {'name': 'Tom', 'gender': 'male'}

#定义一个字典
my_dict ={"name":"Tom","age":18,"gender":"male"}

# 删除字典中的任意一个键值对，并返回对应的键值对
key,value =my_dict.popitem()
print(key,value)  # 输出 "gender":"male"
print(my_dict) # 输出 {"name":"Tom","age":18}